<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>倒转输出</title>
	</head>
	<body>
		<script>
		var a=prompt("请输入一个正整数");
		for(var i=a.length;i>=0;i--){
			document.write(a.charAt(i));
			
		}
		
		
		
		
		</script>
	</body>
</html>
